Abstract

Abstract.
Lattice-selective etching of silicon is used in a number of applications, but it is particularly valuable in those for which the lattice-defined sidewall angle can be beneficial to the functional goals. A relatively small but important niche application is the fabrication of tip characterization standards for critical dimension atomic force microscopes (CD-AFMs). CD-AFMs are commonly used as reference tools for linewidth metrology in semiconductor manufacturing. Accurate linewidth metrology using CD-AFM, however, is critically dependent upon calibration of the tip width. Two national metrology institutes and at least two commercial vendors have explored the development of tip calibration standards using lattice-selective etching of crystalline silicon. The National Institute of Standards and Technology standard of this type is called the single crystal critical dimension reference material. These specimens, which are fabricated using a lattice-plane-selective etch on (110) silicon, exhibit near vertical sidewalls and high uniformity and can be used to calibrate CD-AFM tip width to a standard uncertainty of less than 1 nm. During the different generations of this project, we evaluated variations of the starting material and process conditions. Some of our starting materials required a large etch bias to achieve the desired linewidths. During the optimization experiment described in this paper, we found that for potassium hydroxide etching of the silicon features, it was possible to independently tune the target linewidth and minimize the linewidth nonuniformity. Consequently, this process is particularly well suited for small-batch fabrication of CD-AFM linewidth standards.

MultiMedia

Shibboleth is an access management service that provides single sign-on to protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Copyright in the material you requested is held by SPIE (unless otherwise noted).
This email ability is provided as a courtesy, and by using it you agree that you are requesting the material
solely for personal, non-commercial use, and that it is subject to SPIE'sTerms of Use.
The information provided in order to email this topic will not be used to send unsolicited email, nor will it be
furnished to third parties. Please refer to SPIE'sPrivacy Policy for further information.

Shibboleth is an access management service that provides single sign-on to protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Shibboleth is an access management service that provides single sign-on to protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Shibboleth is an access management service that provides single sign-on to protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Shibboleth is an access management service that provides single sign-on to protected resources. It replaces the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.

Access to SPIE eBooks is limited to subscribing institutions and is not available
as part of a personal subscription. Print or electronic versions of individual SPIE
books may be purchased via SPIE.org.

Shibboleth is access management services that provide single sign-on to protected resources. It replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Shibboleth authentication, please contact your site administrator to receive your user name and password.